Computer operating systems operate generally to control and manage the resources of a computer system. Typically, execution of an operating system is initiated upon power-on or reset of the computer system by a sequence of events known as "bootstrapping" or "booting." The operating system is "booted" by execution of a portion of code stored in a boot sector (which is typically at a fixed location) on a storage medium such as a hard disk drive. Such code is generally referred to as boot code. The boot sector is typically within a portion of the hard disk drive known as the boot partition. The boot code then calls the main operating system code which is stored in different sectors in the boot partition.
If the operating system fails to boot, it is often difficult to determine the cause of the failure. Any diagnosis capability built into the main operating system code is unusable, as the operating system itself is not yet operational.
A known way to diagnose a failed operating system boot is to cause the computer system to boot from a different storage medium such as a floppy diskette typically referred to as a "rescue diskette." In a Windows operating system available from Microsoft Corporation, the presence of a floppy diskette in the "A" drive causes the system to attempt to boot from the "A" drive. Thus, if a failed system boot from the hard disk drive occurs, the user can turn off the system, insert a diskette into the A drive, and attempt a reboot. The floppy diskette must contain a replica of the boot code stored in the boot partition of the hard drive. In addition, the floppy diskette can contain utility programs which can operate to help diagnose the cause of the failure.
There are several problems associated with the use of a rescue diskette. The first problem is that users often misplace or lose the rescue diskette, rendering it useless. The second problem is that the space limitations of a floppy diskette allow only a limited number of files to be stored, thus limiting the diagnosis capability. Multiple floppy diskettes can be used to store additional information. However these additional diskettes increase the odds of losing or misplacing one of the diskettes.
The Windows 95 operating system available from Microsoft Corporation has the ability to determine that a previous attempt to boot the operating system failed. When this happens, Windows 95 boots into a special mode called safe mode. However, once the operating system enters safe mode the user is offered no assistance in diagnosing and correcting the reason for the boot failure. Many users have no idea what to do when the operating system is in safe mode. In most cases the user will simply attempt to restart the system. In such a case, since the user made no changes to the system, the operating system will once again fail to boot and the user will once again be dropped back into safe mode.
As can be seen, there exists a need for a reliable and easy to use system which diagnoses the cause of a failed operating system boot failure and which guides the user through a process to correct the failure.